The present invention relates to fixing devices for fixing a seat to a vehicle floor, and to seats equipped with such fixing devices.
More particularly, the invention relates to a fixing device for fixing a seat to a vehicle floor, the seat having a seat proper which extends between a front end and a rear end, and the device comprising firstly a base designed to support the seat proper and which extends horizontally between a front end and a rear end, and secondly a rear coupling and a front coupling that are secured to the base, the front coupling comprising:
an anchoring fork provided firstly with a first notch designed to co-operate with a rear rod secured to the floor when the seat proper is in an in-use position in which the rear coupling co-operates with fixing means on the floor to hold the seat proper substantially horizontal, and secondly with a second notch designed to co-operate with a front rod secured to the floor when the seat proper is in a tilted-forwards position in which the rear coupling no longer co-operates with the fixing means on the floor so as to allow the seat proper to be inclined relative to the horizontal; and
first and second hooks mounted on the anchoring fork to move between an unlocked position and a locked position in which said first hook and second hook respectively co-operate with the first notch and the second notch to form first and second closed recesses, the rear rod and the front rod being held captive respectively in the first closed recess and in the second closed recess when the seat is in the tilted-forwards position.
Such fixing devices are known, in particular from Patent Application FR 2 783 470. With that type of fixing device, when the seat proper is moved from its in-use position to its tilted-forwards position, the first notch pivots firstly about the rear rod, and then during the movement, the pivot axis is transferred to the front rod so that the second notch pivots about said front rod. While the pivot axis is being transferred, the first notch slides along the rear rod until the first hook holds said rear rod captive substantially at the opening in the first notch. The rear rod thus moves inside the first notch while the seat proper is being moved between its in-use position and its tilted-forwards position. Similarly, when the seat proper is put in place on the floor of the vehicle, the first hook holds the rear rod captive at the opening in the first notch. Therefore, when the seat is brought directly into its in-use position, the rear rod as held captive by the first hook can no longer move along the first notch, which prevents the rear coupling on the base from being placed in register with a fixing member secured to the floor for the purpose of enabling the seat proper of the seat to be fixed to the floor of the vehicle.
It can thus be understood that with that type of fixing device, when the seat proper is brought directly into its in-use position after it is put in place, it is not guaranteed that the seat is locked to the floor of the vehicle, or more exactly, it is not guaranteed that the rear coupling of the base is locked to the floor of the vehicle, which can cause the seat to be tilted accidentally from its in-use position towards its tilted-forwards position.
A particular object of the present invention is to mitigate those drawbacks by providing a fixing device for fixing a seat to a vehicle floor, which device is easy to put in place on the floor, while guaranteeing that the seat proper is properly locked in its in-use position, i.e. relative to the floor of the vehicle.
To this end, in the invention, in a fixing device of the type in question, the first hook is adapted to be in its locked position while holding the rear rod captive in the first closed recess when the seat proper is put in place on the floor of the vehicle, and when the seat proper is in the tilted-forwards position and in the in-use position, and the seat proper pivots about the rear rod only, between its tilted-forwards position and its in-use position.
In preferred embodiments of the invention, any of the following provisions may optionally be used:
the first and second hooks are urged by resilient means into their locked positions, and each of the first and second hooks has a cam surface adapted to come to bear against the rod that is associated with it to cause the corresponding hook to move into its unlocked position while causing the closed recess to open temporarily until the corresponding rod is held captive;
the first notch has an end-wall against which the rear rod bears while the seat proper is pivoting between its tilted-forwards position and its in-use position;
the first and second hooks are formed from a single plate mounted to pivot on the anchoring fork, and the resilient means comprise a spring having a first end fixed to the plate and a second end fixed to the anchoring fork to enable the first and second hooks to be returned resiliently to their locked positions;
the first hook is formed on a first arm mounted to pivot on the anchoring fork about a first pivot and the second hook is formed on a second arm mounted to pivot on the anchoring fork about a second pivot, the resilient means comprise a spring having a first end fixed to the first arm and a second end fixed to the anchoring fork so as to enable the first hook to be returned resiliently to its locked position, and the first and second arms have shapes adapted so that, when the first hook is urged into its locked position by the spring acting on the first arm, the first arm can push the second arm away, thereby bringing the second hook into its locked position;
the second arm is provided with a handle member to enable the second hook to pivot temporarily into its unlocked position, said second arm being adapted to push the first arm away, thereby bringing the first hook into its unlocked position;
the anchoring fork is provided with a guide tip designed to co-operate with the rear rod on the floor, while the seat proper is being put in place on said floor so as to bring the cam surface of the first hook into register with the rear rod;
the first and second notches of the anchoring fork are of oblong shape, are open towards the front of the seat, and extend horizontally-when the seat is in the in-use position; and
the base comprises at least one first rail on which the front coupling and the rear coupling are mounted, and a second rail mounted to slide on the first rail, and which is designed to be fixed to the seat proper of the seat to enable the seat proper to move forwards and backwards.
In addition, the invention also provides a vehicle seat having a seat proper which is mounted on the floor of the vehicle by means of at least one fixing device as defined above.